Mold for centrifugal castings



Patented July 3@, 3. .929.

ears

MOLD FOB CENTEHUGAL CAS'EHJGS.

No Drawing.

ployed for this purpose must be highly heatreslstant in addition to having the required tensile strength. It is customary to make molds for centrifugal casting of a chromenickel steel. One method employed for the manufacture of a mold of this character is" to rough for e a large ingotinto the shape of a round b oom. This bloom is then bored by means of a hollow drill, producing a hollow cylinder with a machined interior. This cylinder is then subjected to the necessary heat treatments to complete the mold.

centrifugal casting can be made from a man.-

- ganese steel alloy containing preferably not less than 13% manganese to which some nickel may be added, preferably not less than 3%.

- This percentage of manganese is sufficient to render thesteel austenitic. Austenitic steel is more heat resistant and wears'better than non-austenitic steel and, therefore, is particularly adaptable for the use herein specified.

an The fiddltlOl'l of the nickel reduces the liability of the molds made from this alloy crackingunder the rapid changes in temperature to which they are subjected in use.

In carryingout my invention I may employ 15 any suitable method for making a mold from the alloy, but I prefer to cast it by the centrifugal method and then to finish it by rolling it into the shape of a seamless tube by means of any of the now existing methods, such as 40 thePilger, automatic or similar processes for rolling seamless tubes. Austenitic steels, of

which the alloy herein specified is one, usually can not be readily machined. I have found,

however, that this rolling method is particunickel, substantially as Application filed February as, 1925. semi no. 12,450;

larly adapted for finishing and shaping an e5 austenitic-steel. v

While-the mold of the present invention is particularly adapted for centrifugal casting because of its high heat resistance and its superior wearing qualities, its use is not limited in this respect as it may be employed for other similar uses where these characteristics are desirable.

I claim:

1. A mold for use in the manufacture of centrifugal castings of iron and steel or other metals having high melting points, consisting substantially of austenitic manganese steel, substantially as described.

2. A mold for use in .the manufacture of centrifugal castings of iron and steel or other metals having high melting points, consisting substantiallyof manganese steel containing I have discovered that a Superior mold for.

at least 13% manganese, substantially as described.

. '3. A mold for use in the manufacture of centrifugal castings of iron and steel or other metals having high melting points, consisting substantially of austenitic manganese steelcontaining a relatively small quantity of 7 nickel the minimum proportion of manga- 'nese exceeding the minimum proportion of nickel, substantially as described.

4. A mold for .use in the manufacture of centrifugal castings of iron and steel or other 75 metals having high melting points, consisting substantially of austenitic manganese steel containing a. relativel small amount of d escribed.

5..A mold for use in the manufactureof centrifugal castings of iron and steel 'or other metals having high melting points, consisting substantially of manganese steel containing at least 13% manganese and at least 8% nickel, substantially as described.

In testimony whereof I have hereunto set my hand. y

' GUSTAV A. REINHARDT. 

